Method of producing oxides of nitrogen



Patented Oct. 20, 1925.

PATENT OFFICE.

HEITRIK GUSTAV ALLAN RAMSAY, LINKOPING, SWEDEN, ASSIGN'OR TO STOCK-HOLMS SUPERIOSFAT FABRI'KS AKTIEBOLAG, A CORPORATION OF SWEDEN.

METKOD OF IPRODUCING OXTDES 0F NITROGEN.

No Drawing.

if necessary mixedfwith other inert gases,

such as carbonic acid at ordinary or re- I duced pressure.

The lime nitrogen or other metal cyanamide or cyanide may be used aloneor" mixed with one or several substances that are able to facilitate thecombustion, due

to catalytic or other-action, or with solid inert substances adapted toregulate the temperature, such' as lime,

oxide or other metal oxides.

he may also add to the charge theresidue from a foregoing operation. Itis suitable but not nec essary to inject pulverous lime nitrogen orother startingmaterial into the combustion chamber, air, oxygen orozone, suitably spreheated, being forced. through the oxidation chamberin the same direction as. or in the opposite direction 'to the pulverousmaterial.

Although the invention may be carried on at atmospheric pressure, thebest results are ,obtained at a reduced pressure.

but.hitherto executed experiments seem to show that good results may beobtained between 600 and 1000 C. and that the best results are obtainedat 850950 C. At temperatures above 1000 C. a destruction of thenheatingof the reaction chamber is required. Probably, it will in practice benecessary to cool the reaction apparatus, so that heat, from the processmay be utiliized for other purposes.

In the execution of the process the best Oxides of,

uartz, ferric The temperature may vary withln wide limits,

Application filed September 20, 1923. Serial No. 663,925.

,.original amount of nitrogen. The air was dried, but this is notnecessary.

2. Pulverous lime nitrogen was forced through a tube of the characterset forth under 1 which was kept heated at 950 C.-

The pressure Within t e tube was reduced to 90 millimeter column ofmercury and pure oxygen was forced through the same.

*An output of 42.5 percent of the original amount of nitrogen wasobtained.

3. This experiment ,.Was executed as set forth under 1 with thedifference that pure oxygen was used. An output of 7 per cent nitrogenas the oxides of nitrogen was obtained.

The concentration of the oxides of nitrogen was sufiicient for technicalpurposes.

The expression metallic compounds which contain CN is used as agenericexpression formetallic c namides (such as calcium cyanamide CalLCN) or'cyanides (such as calcium-"cyanide Ca(CN) I claim 1. Method ofproducing oxides of .nitrogen, consisting in\burning solid metalliccompounds which contain ON in presence I of an oxygen containing gas.

2. Method (if producing oxides of nitrogen, consisting in burningpulverous metallic cyanamldes 1n' the presence of an oxygen containinggas.

A 3. Method of producing oxides of nitrogen, consistlng 1nburnmgpulverous lime n1- trogen (calcium cyanam'lde) lnthe presence ofair.

4. Method of producing oxides of nitrogen consisting in burningpulverous lime nitrogen in the presence of'air at a pressure lower thanthat of the atmosphere.

5. Method of producing oxldes of nitrogen consisting in mixing pulveroussolid acterized by the fact that the pulverous' solid metallic compoundwhich contains CN is mixed with the residue from a foregoing operationbefore being burnt in the presence of an oxygen containing gas 7. Methodaccording to claim 1', characterized by the fact that the reaction isexecuted at temperatures between 600 and 8.Method according to claim 1,characterized by the fact that the gaseous substance containing oxygenis dried before being brought into contact withthe solid substance to beburnt. y

9. Method of producing oxides of nitrogen consisting inburning pulveroussolid metallic compounds which contain GN in the presence of an oxygencontaining gas mixed withan inert gas.

10. Method. of producing oxides of nitrogen consisting in burningpulverous lime nitrogen in the presence of an oxy en containing gasmixed with carbonioacid.

In testimony whereof I have afiixed my signature.

HENRIK' GUSTAV ALLAN 'RAMSAY.

